Computer Science Canada

Why Pointers

Author:  Danjen [ Tue Dec 12, 2006 10:44 pm ]
Post subject:  Why Pointers

In what situation would you use pointers and what are they? As far as I can tell, they are just used to check the next value in a sequence. Confused

Author:  ericfourfour [ Tue Dec 12, 2006 10:50 pm ]
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When dealing with variables, why send an entire copy of a variable if you only need a reference to its location?

Author:  Danjen [ Tue Dec 12, 2006 10:56 pm ]
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So like, it lets you get the value of a variable without typing in that variable's specific name??

Author:  ericfourfour [ Tue Dec 12, 2006 11:08 pm ]
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If you want to be simple, I guess that sums it up.

In Turing you can dereference but you cannot reference. That is one of the downsides of Turing. Sad There is a function called addr but it returns the address as an integer, not a pointer.

Dereference gets the variable the pointer is pointing to. Reference gets a pointer pointing to the variable.

To dereference use:
code:
^pointer_name


A pointer inside a record:
code:
^ (record_name.pointer_name)

Author:  Danjen [ Wed Dec 13, 2006 9:13 am ]
Post subject: 

Ah, okay that clears it up then Smile

Author:  Tony [ Wed Dec 13, 2006 11:45 am ]
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Danjen wrote:
So like, it lets you get the value of a variable without typing in that variable's specific name??


Better yet, you can switch where the pointer points to, and perform the same operations on a different "variable", without really needing to know which one exactly it is.


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